Pick over the cress and remove the stems; wash the leaves several times in plenty of water and drain.

Pick over the spinach and remove the stems; wash the leaves several times in plenty of water, then dry in a salad spinner.

Preheat the oven to 260° C (500° F) and an electric element to 150° C (300° F). Peel the shallots, chop them finely and set them aside on a saucer.

Preparing the lobsters

Using a mallet, lightly crack the lobster claws (to make them easier to shell after cooking).

Place the lobster in a baking dish and coat with 2 tbsp. olive oil.

Preparing the reduction

Place a pan containing 5 g (1 tsp.) butter on the preheated element.

When the butter is hot, add the chopped shallots. Stir with a wooden spoon for 2 to 3 minutes until they are transparent.

Add the vinegar and white wine, combine and reduce for about 10 minutes (there should be 2 tbsp. of liquid remaining.)

Cooking the lobster

Place the dish containing the lobsters into the oven and cook for 12 minutes.

Warm the serving platter (or plates) and the sauceboat.

Take 100 g (7 tbsp.) butter from the refrigerator and preheat an electric element to 70° C (150° F).

Making the vanilla beurre blanc

On the cutting board, split the vanilla beans in half lengthwise and set the four halves aside on a saucer.

When the reduction is ready, place the pan on the element (70° C) and add the butter one small piece at a time, whisking constantly, until it is all incorporated.

You should obtain a very smooth mixture. Season with 2 1/2 pinches of salt and 4 grinds of fresh pepper, then, off the heat, scrape the insides of the split vanilla beans into the beurre blanc and whisk again so that the sauce is flavored with the vanilla.

Cooking the spinach and cress

Place a saucepan containing 10 g (2 tsp.) of butter on an element (100° C / 200° F). When the butter is hot, add the spinach and cress leaves, season with 3 pinches of salt and 4 grinds of fresh pepper, combine well, cook for about 3 minutes, then turn off the heat.

Cutting up the lobster

Remove the cooked lobsters from the oven, place them on a cutting board and shell the legs and claws to remove the meat.

Separate the tail from the head and remove the tail meat. Take out the intestine which is found on the top of the tail.

Cut the lobster meat into medallions 5 to 8 mm (1/4 to 1/3”) thick.

Finishing and presentation

Place the spinach and cress on a serving platter (or divide among individual plates). Arrange the lobster meat on this bed.

Season with 3 pinches of salt and 4 1/2 grinds of fresh pepper, and place the dish into the oven for a few minutes to keep hot.

Reheat the beurre blanc while whisking it, then pour it through a strainer placed over the warmed sauceboat.